Relationship between pH and Some Components of Rain Waters in Tokushima City

Abstract

The rain waters in Tokushima city from June 1988 to May 1989 were analyzed concerning pH value, electric conductivity (EC), and concentrations of some ions. There was a V-shaped relationship between pH and EC that had minimum value at pH 5.6-6.0. Namely, EC increased with the decrease of pH under the value, whereas it increased with the increase of pH value at pH more than 5.0. There were similar relationships between pH value and sulfate, nitrate, calcium, or ammonium ion concentrations. Moreover, there was a good relationship between sulfate and nitrate ion concentration. The rain waters in typhoon contained high concentrations of chloride, sodium, and calcium ions.